Novel photographic processes, compositions and products



United States Patent 3,218,164 NOVEL PHOTOGRAPHIC PROCESSES, COMPOSI- TIONS AND PRODUCTS Milton Green, Newton Highlands, and Leon E. Rubin,

Canton, Mass, assignors to Polaroid Corporation, Cambridge, Mass., a corporation of Delaware N0 Drawing. Filed Jan. 26, 1959, Ser. No. 788,728 23 Claims. (Cl. 96-29) This invention relates to photography and more particularly to products, compositions and processes for the development of photosensitive silver halide elements.

It is one object of the present invention to provide novel processes and compositions for the development of silver halide emulsions, in which colored developing agents are used to develop a latent image.

Another object is to provide novel processes and compositions for the development of silver halide emulsions, in which the novel developing agent is capable of developing a latent image and imparting a reversed or positive colored image of said latent image to a superposed imagereceiving material.

A further object is to provide novel products, processes and compositions suitable for use in preparing monochromatic and multichromatic photographic images.

A still further object is to provide dye developers with increased stability against the deleterious effects of actinic radiation.

A still further object is to provide dye developers with increased stability against the deleterious effects of humidity and/ or temperature variations.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the processes involving the several steps and the relation and order of one or more of such steps with respect to each of the others, and the products and compositions possessing the features, properties and the relation of elements which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

The novel photographic developing agents employed in this invention possess the properties of both a dye and a developing agent; thus they may be referred to as dye developers. The nature of these dye developers will be described hereinafter.

The photographic processes and compositions disclosed herein are particularly useful in the treatment of a latent image present in a photosensitive element, such as an exposed silver halide emulsion, whereby a positive dye image thereof may be imparted to another element, herein referred to as an image-carrying or image-receiving element.

The copending application of Howard G. Rogers, Serial No. 748,421, filed July 14, 1958, now US. Patent 2,983,606 issued May 9, 1961, discloses diffusion transfer-reversal processes wherein a photographic negative material, such as a photographic element comprising an exposed silver halide emulsion layer containing a latent image, is processed using a dye developer to impart to an image-receiving element a reversed or positive dye image of said latent image by permeating into said emulsion layer a suitable liquid processing composition and bringing said emulsion layer into superposed relationship with an appropriate image-receiving layer. It is an object of this invention to provide additional dye developers suitable for use in such processes.

In carrying out the process of this invention, a photosensitive element containing a silver halide emulsion is exposed and wetted with a liquid processing composition, for example, by immersing, coating, spraying, flowing, etc., in the dark, and the photosensitive element superposed, prior to, during or after wetting, on a sheetlike support element, which may be utilized as an imagereceiving element. In a preferred embodiment, the photo sensitive element contains a layer of dye developer, and the liquid processing composition is applied to the photosensitive element in a uniform layer as the photosensitive element is brought into superposed position with an image-receiving element. It is also within the scope of this invention to apply the liquid processing composition prior to exposure, in accordance with the disclosure in the copending application of Edwin H. Land, Serial No. 498,672, filed April 1, 1955, now Patent No. 3,087,816. The liquid processing composition permeates the emulsion to provide a solution of dye developer substantially uniformly distributed therein. As the latent image is developed, the oxidation product of the dye developer is immobilized or precipitated in exposed areas, thereby providing an imagewise distribution of unoxidized dye developer dissolved in the liquid processing composition. This immobilization is apparently, at least in part, due to a change in the solubility characteristics of the dye developer upon oxidation, and especially as regards its solubility in alkaline solutions. It may also be due, in part, to a tanning effect on the emulsion by the oxidized developing agent and to localized exhaustion of alkali due to development. At least part of this imagewise distribution of unoxidized dye developer is transferred, by imbibition, to a superposed image-receiving layer or element, said transfer substantially excluding oxidized dye developer. Under certain circumstances, the layer of the liquid processing composition may be utilized as the imagereceiving layer. The latter element receives a depthwise diffusion, from the emulsion, of unoxidized dye developer without appreciably disturbing the imagewise distribution thereof to provide a reversed or positive, colored image of the developed image. The image-receiving element may contain agents adapted to mordant or otherwise fix the diffused, unoxidized dye developer. If the color of the diffused dye developer is affected by changes in the pH of the image-receiving element, this pH may be adjusted in accordance with well-known techniques to provide a pH affording the desired color. Imbibition periods of approximately one minute have been found to give good results, but this contact period may be adjusted where necessary to compensate for variations in temperature of other conditions. The desired positive image is revealed by stripping the image-receiving element from the photosensitive element at the end of the imbibition period.

The dye developers of this invention may be utilized in the photosensitive element, for example in, on or behind the silver halide emulsion, or they may be utilized in the image-receiving element or in the liquid processing composition. In a preferred embodiment, a coating or layer of the dye developer is placed behind the silver halide emulsion, i.e., on the side of the emulsion adapted to be located most distant from the photographed subject when the emulsion is exposed and preferably also adapted to be most distant from the image-receiving element when in superposed relationship therewith. Placing the dye developer behind the emulsion layer, as in the preferred embodiment, has the advantage of providing increased contrast in the positive image, and also minimizes any light filtering action by the colored dye developer. In this preferred embodiment, the layer of dye developer may be applied by using a coating solution containing about 0.5 to 8%, by weight, of the dye developer. Similar concentrations may be used if the dye developer is utilized as a component of the liquid processing composition, concentrations as low as 0.2% in the liquid processing com position being suitable in certain instances.

The liquid processing composition above referred to comprises at least an aqueous solution of an alkaline compound, for example, diethylamine, sodium hydroxide or sodium carbonate, and may contain the dye developer. In some instances, it may contain a conventional developing agent. If the liquid processing composition is to be applied to the emulsion by being spread thereon, preferably in a relatively thin, uniform layer, it may also include a viscosity-increasing compound constituting the film-forming material of the type which, when said composition is spread and dried, will form a relatively firm and relatively stable film. A preferred film-forming ma terial is a high molecular weight polymer such as a polymeric, water-soluble ether inert to an alkali solution, as for example, hydroxyethyl cellulose or sodium carboxymethyl cellulose. Other film-forming materials or thickening agents whose ability to increase viscosity is substantially unaffected when left in solution for a long period of time may also be used.

It has now been discovered that dye developers which form stable coordination complexes with metals may be complexed to provide dye developers exhibiting increased stability against the color degradation effects of actinic radiation, humidity and/ or temperature variations.

Generally, dye developers which form stable coordination complexes with metals belong to two main classes, that is, azo and anthraquinone dye developers. The dye developers all exhibit the common feature of possessing a chelatable group, as for example:

wherein R is an alkyl or hydroxyl group; by means of which a chelate ring may be formed, for example, between an azo, hydroxyl or carboxyl group and a metal atom covalently attached to the oxygen atom of a phenolic or enolic hydroxyl group.

In general, the aforementioned complexing may be accomplished as a result of complexing the appropriate dye developer with a chelating metal, preferably a metallic ion derived from an ionizable salt or a chelate exhibiting less stability than the dye developer chelate ultimately desired.

According to the preferredembodiment of the present invention, monoand disazo dye developers containing hydroxyl and/ or carboxyl radicals substituted, respectively, on aryl nuclei at positions ortho and ortho and to an azo group form stable coordination complexes as a result of contacting the appropriate dye developer with a nickel,

wherein R is selected from the group consisting of hydrogen, aliphatic and aromatic groups; R is selected from the group consisting of aliphatic and aromatic groups; X and Y each may be the same or different and are selected from the group consisting of O- and =NOH groups; and Z is a metallic atom selected from the group consisting of copper and nickel; for example a nickel or copper chelate of an enolizable B-diketone, such as acetylacetone, an enolizable fl-keto ester, such as ethyl acetoacetate, an enolizable [i-ketoxime, such as dibenzoylmethane monoxime, or a ,B-ketoaldehyde.

A preferred, group of dye developers comprises the metallized, that is, metal-complexed, dye developers of the formula:

wherein A represents a benzenoid developing group; B is a covalent bond or a divalent radical; y is 1 or 2; and each Ar, which may be the same or difierent, represents an aryl or heterocyclic group, at least one of said group containing a hydroxyl or carboxyl group substituted in ortho position to the azo group.

As examples of aryl and heterocyclic groups, signified by the term Ar in Formula A, suitable for use in the practice of the present invention, mention may be made of: phenyl, naphthyl, pyrazolone, etc., and the substituted.

derivatives thereof.

Examples of groups which may be present in such substituted derivatives include alkyl, sulfo, alkoxy, aryl, aryloxy, amino, keto alkylamino, arylamino, hydroxyl, cyano, alkylamido, arylamido, carboalkoxy, carboxamido, sulfonamido, etc.

One preferred class of dye developers within Formula A comprises the metal-complexed dye developers of the formula:

OH B l ,N=N-Ar' wherein B has the same significance as previously set forth;

Ar represents an aryl or heterocyclic group which contains a hydroxyl or carboxyl group substituted in ortho position to the azo group; and X represents the carbon atoms necessary to complete a benzene or naphthalene nucleus, which nucleus may have additional substituents Where desired.

It must be noted that the protected derivatives of the aforementioned benzenoid developing groups may be employed during the complexing reaction to afford protection to said groups by isolating them from reaction. For example, in the aforementioned general preparation where the benzenoid developing groups comprise hydroxyl substituted benzene or naphthalene nuclei, it is preferable that said hydroxyl groups be protected during reaction, as for example, by acylation, such as carbethoxylation, acetylation, etc. Where desired, as for example, for use as photographic dye developers, the hydroxyl groups may be reconstituted by deesterification of the respective acyloxy protective groups subsequent to the complexing reaction, for example, by hydrolysis in the presence of alkali.

The term acyloxy as used herein is intended to signify the grouping:

o ra ii-owherein R is an aryl, alkyl, aryloxy or alkoxy group.

As examples of benzenoid developing groups contemplated suitable for use in the practice of this invention to provide the benzenoid developing portion of the dye molecule, mention may be made of: benzene and naphthalene nuclei so substituted by at least two groups selected from the group consisting of hydroxyl and amino groups as to be capable of developing an exposed silver halide emulsion, as for example, polyphenols such as p-dihydroxybenzene, o-dihydroxybenzene; aminophenols such as 2-amin0- phenol; aminonaphthols such as 4-amino-1-naphthol; polyamines such as 1,4-diaminobenzene; and the substituted derivatives thereof. Benzenoid developing groups comprise aromatic nuclei so substituted as to form quinone or quinonoid products upon oxidation.

The term amino as used above is intended to include amino groups so substituted as not to impair their respective silver halide developing functions, as for example, suitably susbtituted alkylamino and arylamino groups.

The preferred benzenoid developing group comprises a p-dihydroxy-phenyl group. The respective benzenoid developing group or groups and the acyloxy protective derivatives thereof may be linked to the chromophore containing component of the dye molecule by utilization of a divalent radical or a covalent bond. As examples of divalent radicals, suitable for use in the practice of this invention, mention may be made of: divalent organic radicals such as alkylene radicals, preferably lower alkylene radicals such as ethylene, propylene, etc.; arylene radicals such as phenylene, etc.; acyl radicals such as etc.; alkarylene radicals such as etc.; and divalent radicals which contain both hetero and carbon atoms as constituent components of said radicals such as etc., radicals.

According to another embodiment of the present invention, monoand disazo dye developers containing a hydroxyl or carboxyl radical substituted on an aryl nucleus 2- (4- [4"- 2",5"-dihydroxyphenethyl -phenylazo] naphthaleneazo -4-methoXy-1-naphthol,

p-( 1-hydroxy-4-meth-oxy-2-naphthalene azo -phenethylcatechol,

2- p- [3- hydroquinonyl -ethyl] -phenylazo -4-methoxyl-naphthol,

2- p- [5- (hydroquinonyl -ethy1] -phenylazo) -4-npro poxy-l-naphthol,

the preparations of which are disclosed in the copending US. application of Elkan R. Blout, Milton Green, and Howard G. Rogers, Serial No. 612,045, filed September 25, 1956, and abandoned in favor of Serial No. 144,816,

filed October 18, '1961, a continuation-in-part thereof, which is now Patent No. 3,134,672;

2-( 2',5'-dimeth0xy-4- [p- 2",5 "-dihydroxyphenyl) -pheny-lazo] -phenylazo)-4-methoxy-1-naphthol,

the preparation of which is disclosed in the copending US. application of Helen P. Husek and Myron S. Simon, Serial No. 612,054, filed September 25, 1956, and abandoned in favor of Serial No. 197,283, filed May 24, 1962, a continuation-in-part thereof;

2- 2',5 '-dimethoxy-4'- [p- 2",5 "-dihydroxyphenethyl phenylazo] -phenylazo -4-meth oxy- 1 -naphthol,

the preparation of which is disclosed in the copending US. application of Helen P. Husek, Serial No. 612,055, filed September 25, 1956, and abandoned in favor of Serial No. 192,354, filed May 4, 1962, a continuation-inpart thereof, which is now Patent No. 3,134,762, and Serial No. 192,355, filed May 4, 1962;

2- (p- [4'-methyl-2',5 '-dihydroxyphenylthioethyl -phenylazo]-4-methoxy-1-naphthol,

the preparation of which is disclosed in the copending US. application of Milton Green and Howard G. Rogers, Serial No. 663,905, filed June 6, 1957, and abandoned in favor of applications Serial No. 193,293 and 193,326, both filed May 8, 1962, as continuations-in-part thereof;

2- (p- [2",5"-dihydroxyphenoxy]-phenylazo)-4-methoxyl-naphthol,

the preparation of which is disclosed in the copending US. application of Milton Green, Serial No. 680,403, filed August 26, 1957, now abandoned;

2- p- [hydroquinonylsulfonyl] -pheny1azo -4-methoxyl-naphthol,

the preparation of which is disclosed in the copending US. application of Milton Green, Serial No. 680,434, filed August 26, 1957, and abandoned in favor of Serial No. 230,287, filed October 12, 1962 as a continuation-inpart thereof;

the preparation of which is disclosed in the copending US. application of Elkan R. Blout, Milton Green, Howard G. Rogers, and Myron S. Simon, Serial No. 685,081, filed September 20, 1957, and abandoned in favor of Serial No. 222,702, filed September 10, 1962, a continuation-in-part thereof, and Serial No. 222,656, filed September 10, 1962 and now Patent No. 3,142,565;

the preparation of which is disclosed in the copending US. application of Milton Green, Serial No. 703,515, filed December 18, 1957, and now abandoned;

4,4'-bis-(4"- [2,5"-dihydroxyphenethyl]-phenylsulfamyl)-1-hydroxy-1,2-azonaphthalene,

4- (4-[2",5-dihydroxyphenethyl] -N-methyl-phenylsulfamyl)-2-(2',5'-dimethoxyphenylazo)-1-naphthol,

the preparations of which are disclosed in the copending US. application of Elkan R. Blout, Milton Green, Howard G. Rogers, and Robert B. Woodward, Serial No. 707,109, filed January 6, 1958 and now abandoned;

2-(4'-[4"-(2",5"-dihydroxyphenethyl)-phenylcarbarnyl]-pl1enylazo)-4-methoxy-1-naphthol,

the preparation of which is disclosed in the copending US. application of Milton Green and Howard G. Rogers, Serial No. 748,145, filed July 14, 1958, and abandoned in favor of Serial No. 190,804, filed April 27, 1962, a continuation-in-part thereof; and 1-(4'-[2",5"-dihydroxyphenethyl]-2'-hydroxyphenylazo)-4-methoxy-1-naphthol,

7 the preparation of which is disclosed in the copending US. applications of Milton Green and Myron S. Simon, Serial No. 788,893, filed January 26, 1959, and abandoned in favor of Serial No. 359,998, filed April 15, 1964.

According to still another embodiment of the present invention monoazo, disazo and anthraquinone dye developers, characterized in that they contain preferably an o-dihydroxyphenyl group or salicylic acid group, may be stabilized against the color degradation effects of actinic radiation, humidity and/ or temperature variations by the formation of stable metallic coordination complexes by appropriate chelation of said o-dihydroxyphenyl group or salicylic acid group.

A still further embodiment of the present invention comprises forming stable metallic cordination complexes of anthraquinone dye developers. For example, anthraquinone dye developers substituted in an tar-position by hydroxyl groups may be suitably complexed with a metallic ion or chelate according to the aforementioned procedures.

The preparations of anthraquinone dye developers having an u-hydroxy substituent are disclosed in the following copending U.S. applications:

Serial No. 478,922, filed December 30, 1954in the names of Elkan R. Blout, Marilyn R. Cohler, Milton Green, Myron S. Simon and Robert B. Woodward, and abandoned in favor of Serial No. 824,785, filed July 3, 1959, continuation-in-part thereof, which in turn was abandoned in favor of continuation-in-part application Serial No. 233,461, filed October 26, 1962, now Patent No. 3,135,606; and also Serial No. 824,786, filed July 3, 1959, which in turn was abandoned in favor of continuation-in-part application Serial No. 318,827, filed October 26, 1963;

Serial No. 485,342, filed January 31, 1955 in the name of Richard S. Corley, now Patent No. 2,983,605; and

Serial No. 771,719, filed November 4, 1958 in the names of Elkan R. Blout and Richard S. Corley, and abandoned in favor of Serial No. 193,320, filed May 8, 1962, a continuation-in-part thereof.

Complexing the respective dye developer intermediates preferably is effected in the presence of heat.

The preferred dye developer of the present invention comprises chromium-complexed 3-homogentisamido-4-(ohydroxyphenylazo)-l-phenyl-S-pyrazolone as prepared in Examples 1 and 2.

The invention will be illustrated in greater detail in conjunction with the following specific examples which set out representative preparations and photographic utilization of the novel compounds of the preferred embodiment of the present invention, which however, is not limited to the details therein set forth which are intended to be illustrative only.

Example 1 To prepare the chromium complex of 3-dicarbethoxyhomogentisamido 4 (o hydroxyphenylazo) 1 phenyl--pyrazolone, 2 g. of 3-dicarbethoxyhomogentisamido- 4-(o-hydroxyphenylazo)-1-phenyl-5-pyrazolone, melting at 227 to 228 C., and 0.6 g. of chromic chloride in 60 cc. of formarnide are heated at 112 C. for 4.5 hours. The warm solution, which has changed from yellow to dark red, is poured into 200 cc. of hot saline solution.

1.25 g. of a red precipitate, the desired product, is obtained, which after filtering and washing to remove the sodium chloride, melts at a temperature in excess of 360 C.

Example 2 To prepare the chromium complex of 3-homogentisamid o-4- o-hydroxyphenylazo 1-phenyl-5 -pyrazolone, the product of Example 1 is dissolvedin a solution of 18 cc. of 95% ethanol and 1 g. of potassium hydroxide in 5 cc. of water and warmed in the absence of air for 2 minutes. The resultant solution is neutralized by the addition of 5 cc. of 6 N sulfuric acid, filtered and washed until acid 8 free. A product yield of 1 g. of the desired metallized dye developer is obtained. This product exhibits a visible absorption spectral peak at 496 my and a molecular extinction coefficient of 15,300 in 95% ethanol.

As previously mentioned, the novel azo dyesof this invention, characterized in that they contain not less than one benzenoid developing group, are useful dye developers. In the following example all parts are given by weight except where otherwise noted, and all operations involving light-sensitive materials are carried out in the absence of actinic radiation. This example is intended to be illustrative only of the photographic use of the dye developers and should not be construed as limiting the invention in any Way.

Example 3 A photosensitive element is prepared by coating a gelatin-coated film base with a solution containing 3% of chromium-complexed 3-homogentisamido-4(o-hydroxyphenylazo)-1-phenyl-5-pyrazolone [as prepared in Examples 1 and 2] in a 4% solution of cellulose acetate hy drogen phthalate in an :20 mixture, by volume, of ace: tone and methanol. After this coating has dried, a silver iodobromide emulsion is applied. This photosensitive element is exposed and processed by spreading an aqueous liquid processing composition comprising:

Percent Sodium carboxymethyl cellulose 4.5 l-phenyl-B-pyrazolidone 0.2 Sodium hydroxide 2.0 Potassium bromide 0.2

between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a polyvinyl butyral-coated baryta paper which has been coated with a solution comprising 4% N-methoxymethyl polyhexamethylene adipamide in 80% aqueous isopropanol. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a red positive dye image of the photographed subject.

It will be noted that the liquid processing composition may, and in the above examples does, contain an auxiliary or accelerating developer such as p-methylaminophenol (Metol); 2,4-diaminophenol (Amidol); benzylaminophenol; or a 3-pyrazolidone, such as 1-pheny1-3-pyrazolidone (Phenidone). The preferred auxiliary developer is 1-phenyl-3-pyrazolidone. This auxiliary developer serves to accelerate and possibly initiate the action of the dye developer. It is possible that some of the dye developer oxidized in exposed areas may be oxidized by an energy transfer reaction with oxidized auxiliary developer.

The dye developers of this invention may be used also in conventional photographic processes, such as tray or tank development of conventional photosensitive films, plates or papers to obtain black and white, monochromatic or toned prints or negatives. By way of example, a de- Veloper composition suitable for such use may comprise an aqueous solution of approximately 1 to 2% of the dye developer, 1% sodium hydroxide, 2% sodium sulfite and 0.05% potassium bromide. After development is completed, any unreacted dye developer is washed out of the photosensitive element, preferably with an alkaline washing medium or other medium in which the unreacted dye developer is soluble. The expression toned is used to designate photographic images wherein the silver is retained with the precipitated dye, whereas monochromatic is intended to designate dye images free of silver. It should be noted that the dye developers of this ini vention are self-sufficient to provide the desired color image and do not depend upon coupling reactions to produce the desired color. They thus provide a complete departure from conventional photographic color processes in which the color is produced by a coupling reaction involving the oxidized developing agent.

The dye developers of this invention are preferably selected with a view to their usefulness in color photography and, in particular their ability to provide the desired subtractive colors, i.e., magenta, yellow or cyan.

It must be noted that metal complexing suitable intermediate dye developers provide a means of elfecting a pronounced shift in the spectral absorption characteristics of the respective intermediate dye developers.

In will be apparent that, by appropriate selection of the image-receiving element from among suitable known opaque and transparent materials, it is possible to obtain either a colored positive reflection print or a colored positive transparency. Likewise, the inventive concepts herein set forth are adaptable for multicolor work by the use of special photographic materials, for example, film materials of the type containing two or more photosensitized elements associated with an appropriate number of imagereceiving elements and adapted to be treated with one or more liquid processing compositions, appropriate dye developers suitable to impart the desired subtractive colors being incorporated in the photosensitized elements or in the liquid processing compositions. Examples of such photographic materials are disclosed in U.S. Patent No. 2,647,049 to Edwin H. Land.-

The inventive concepts herein set forth are also adaptable for the formation of colored images in accordance with the photographic products and processes described in the copending application of Edwin H, Land, Serial No. 448,441, filed August 9, 1954, now Patent No. 2,068,554 and also the copending application of Edwin H. Land and Howard G. Rogers, Serial No. 565,135, filed February 13, 1956.

In the preceding portions of the specification the expression color has been frequently used. This expression is intended to include the use of a plurality of colors to obtain black, as well as the use of a single black dye developer.

Since certain changes may be made in the above products, compositions and processes without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. In a process of forming a photographic image, the steps which comprise developing a latent image contained in an exposed silver halide emulsion with a processing solution comprising an aqueous alkaline solution of an alkali-soluble metal-complexed dye developer, said dye developer being a compound which is both a silver halide developing agent and a metal-complexed dye, immobilizing said metal-complexed dye developer in exposed areas of said emulsion, providing in said emulsion a predetermined distribution of mobile dye developer, and transferring at least part of said distribution of said mobile dye developer, by imbibition, from said emulsion to an imagereceiving element in superposed relationship with said emulsion to impart to said image-receiving element a reversed image of the developed image.

2. The process as defined in claim 1 wherein said aqueous alkaline solition contains an accelerating developing agent.

3. The process as defined in claim 1 wherein said metalcomplexed dye developer is disposed prior to exposure in a photosensitive element containing said emulsion and the solution containing said metal-complexed dye developer is formed by permeating said photosensitive element with an aqueous alkaline liquid capable of solubilizing said metal-complexed dye developer.

4. The process as defined in claim 1 wherein said metalcomplexed dye developer is dissolved in an aqueous alkaline solution prior to application thereof to said exposed emulsion.

5. The process as defined in claim 1 wherein said metalcomplexed dye developer is a metal complex of an azo dye which is also a silver halide developing agent, said azo dye having at least one member of the group consisting of hydroxyl and carboxyl groups substituted in ortho position to an azo linkage of said dye.

6. The process as defined in claim 1 wherein said metalcomplexed dye developer comprises a metal complex of a dye developer of the formula:

wherein B is a lower alkylene radical; Ar is selected from the group consisting of aryl and heterocyclic groups which contain a group selected from the group consisting of hydroxyl and carboxyl groups substituted in ortho position to the azo group; and X represents the carbon atoms necessary to complete a nucleus selected from the group consisting of benzene and naphthalene nuclei.

7. The process as defined in claim 1 wherein said metalcomplexed dye developer is chromium complexed 3- homogentisamido 4 (o hydroxyphenylazo 1 phenyl-S-pyrazolone.

8. A process of developing an exposed photosensitive silver halide emulsion which comprises contacting said emulsion with an aqueous alkaline solution of an alkalisoluble metal-complexed dye developer, said dye developer being a dye which is also a silver halide developing agent.

9. A process as defined in claim 8 wherein said aqueous alkaline solution contains an accelerating developing agent.

10. A process as defined in claim 8 wherein said metalcomplexed dye developer is disposed prior to exposure in a photosensitive element containing said emulsion and the solution containing said metal-complexed dye developer is formed by permeating said photosensitive element with an aqueous alkaline liquid capable of solubilizing said metal-complexed dye developer.

11. The process as defined in claim 8 wherein said metal-complexed dye is a metal complex of an azo dye which is also a silver halide developing agent, said azo dye having at least one member of the group consisting of hydroxyl and carboxyl groups substituted in ortho position to an azo linkage of said dye.

12. A process as defined in claim 8 wherein said metalcomplexed dye developer comprises a metal complexed of a dye developer of the formula:

I OH

wherein B is a lower alkylene radical; Ar is selected from the group consisting of aryl and heterocyclic groups which contain a group selected from the group consisting of hydroxyl and carboxyl groups substituted ortho in the azo group; and X represents the carbon atoms necessary to complete a nucleus selected from the group consisting of benzene and naphthalene nuclei.

13. A process as defined in claim 8 wherein said metalcomplexed dye developer is chromium-complexed 3- homogentisamido 4 (o hydroxyphenylazo) 1 phenyl-5-pyrazolone.

14. A photographic product comprising a support, a silver halide emulsion in a layer on said support, and a metal-complexed dye developer in a layer on the same side of said support as said emulsion, said dye developer being a dye which is also a silver halide developing agent, said dye developer further being soluble in an aqueous alkaline processing solution in its unoxidized form and insoluble in said processing solution in its oxidized form.

15. A photographic product as defined in claim 14 wherein said metal-complexed dye developer and said silver halide emulsion are in the same layer.

16. A photographic product as defined in claim 14 wherein said metal-complexed dye is a metal complex of an azo dye which is also a silver halide developing agent, said azo dye having at least one member of the group consisting of hydroxyl and carbonyl groups substituted in ortho position to an azo linkage of said dye.

17. A photographic product as defined in claim 14 wherein said metalcornplexed dye developer comprises a metal complex of a dye developer of the formula:

wherein B is a lower alkylene radical; Ar is selected from the group consistin of aryl and heterocyclic groups which contain a group selected from the group consisting of hydroxyl and carboxyl groups substituted ortho to the azo group; and X represents the carbon atoms necessary to complete a nucleus selected from the group consisting of benzene and naphthalene nuclei.

18. A photographic product as defined in claim 14 wherein said metal-complexed dye developer comprises chromium'complexed 3 homogentisamido 4 (o hydrophenylazo) -1-phenyl-5-pyrazolone.

19. A photographic product including: (1) a photosensitive element comprising a support, a silver halide emulsion in a layer on said support and a metal-complexed dye developer in a layer on the same side of said support as said emulsion, said dye developer being a dye which is also a silver halide developing agent, said dye developer further being soluble in an aqueous alkaline processing solution in its unoxidized form and insoluble in said solution in its oxidized form; (2) an image-receiving element having a dyeable layer to receive a transfer image in superposed relationship with said photosensitive element; and (3) a frangible container confining a photographic processing composition, said container being so positioned as to be capable of being ruptured and its contents spread uniformly so as to at least partially permeate said photosensitive element.

20. A novel photographic developer composition comprising an accelerating developing agent, an aqueous solution, an alkaline material soluble therein, and an alkalisoluble metal-complexed dye developer.

21. A photographic developer composition as defined in claim wherein said metal-complexed dye is a metal complex of an azo dye which is also a silver halide developing agent, said azo dye having at least one member of the group consisting of hydroxyl and carboxyl groups substituted in ortho position to an azo linkage of said dye.

12 22. A novel photographic developer composition as defined in claim 20 wherein said metal complex of a dye developer comprises a metal dye developer of the formula:

wherein B is a lower alkylene radical; Ar is selected from the group consisting of aryl and heterocyclic groups which contain a group selected from the group consisting of hydroxyl and carbonyl groups substituted in ortho position to the no group; and X represents the carbon atoms necessary to complete a nucleus selected from the group consisting of benzene and naphthalene nuclei.

23. A novel photographic developer composition as defined in claim 20 wherein said metal-complexed dye developer is chromium-complexed 3-homogentisamido-4-(ohydroxyphenylazo )-1-phenyl5-pyrazolone.

References Cited by the Examiner UNITED STATES PATENTS 2,055,407 9/1936 Gaspar 96-99 2,304,884 12/1942 Carroll 1 96-53 2,386,596 10/1945 Crossley et ah 260-206 X 2,533,181 12/1950 Sargent .96-55 2,726,238 12/1955 Morschel et a1. 260-206 X 2,730,521 1/1956 Schetty et al 260146 2,734,052 2/1956 Ditmar et al 260-146 2,774,668 12/1956 Rogers 96-29 2,779,758 1/1957 Neier et a1 260197 X 2,892,710 6/ 1959 Cohler. 2,906,746 9/1959 Brassel et al 260-197 X 2,909,430 10/1959 Rogers. 2,983,606 5/1961 Rogers. 3,081,167 3/1963 Goulston et a1 ...9629 3,134,672 5/1964 Blout et al. 96-29 3,135,604 6/1964 Green et al 96-29 FOREIGN PATENTS 554,212 7/1957 Belgium.

554,933 8/1957 Belgium.

554,934 8/1957 Belgium.

554,935 8/1957 Belgium.

804,971 11/1958 Great Britain.

OTHER REFERENCES Venkataraman: The Chemistry of Synthetic Dyes, 1, Academic Press, New York, 1952, pp. 551-569; 534-40, 553.

NORMAN G. TORCHIN, Primary Examiner.

HAROLD H. BURSTEIN, PHILIP E. MANGAN,

Examiners. 

1. IN A PROCESS OF FORMING A PHOTOGRAPHIC IMAGE, THE STEPS WHICH COMPRISE DEVELOPING A LATENT IMAGE CONTAINED IN AN EXPOSED SILVER HALIDE EMULSION WITH A PROCESSING SOLUTION COMPRISING AN AQUEOUS ALKALINE SOLUTION OF AN ALKALI-SOLUBLE METAL-COMPLEXED DYE DEVELOPER, SAID DYE DEVELOPER BEING A COMPOUND WHICH IS BOTH A SILVER HALIDE DEVELOPING AGENT AND A METAL-COMPLEXED DYE, IMMOBILIZING SAID METAL-COMPLEXED DYE DEVELOPER IN EXPOSED AREAS OF SAID EMULSION, PROVIDING IN SAID EMULSION A PREDETERMINED DISTRIBUTION OF MOBILE DYE DEVELOPER, AND TRANSFERRING AT LEAST PART OF SAID DISTRIBUTION OF SAID MOBILE DYE DEVELOPER, BY IMBIBITION, FROM SAID EMULSION TO AN IMAGERECEIVING ELEMENTE IN SUPERPOSED RELATIONSHIP WITH SAID EMULSION TO IMPART TO SAID IMAGE-RECEIVING ELEMENT A REVERSED IMAGE OF THE DEVELOPED IMAGE. 